• Korean Journal of Organic Agriculture
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• v.13 no.2
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• pp.175-184
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• 2005

This study was conducted to investigate into the distribution of arbuscular mycorrhizal fungi (AMF) in the greenhouse soils grown strawberry plants in Damyang and Jangheung districts. Twenty three soil samples were collected from strawberry plants under greenhouse conditions, and mycorrhizal spores in soils were separated using wet-sieving methods. Number of mycorrhizal spores per 30g fresh soil sized over 500${\mu}$m, 355~500${\mu}$m, 251~354${\mu}$m, 107~250${\mu}$m and $45{\sim}106{\mu}m$ were 0.3, 1.0, 4.2, 50.4 and 119, etc. Total number of spores per 30g fresh soil were l73.9. Root infection by vesicles and hyphae were 25% and 4%, respectively. Mycorrhizal root infection by arbuscules was not shown in strawberry roots. Isolated mycorrhizal spores were inoculated into the host plant of sudangrass to identify the genus of arbuscular mycorrhizal fungi, and propagated for 4 months. As a result of identification, mass propagated mycorrhizal spores were Glomus sp., Gigaspora sp., and Acaulospora sp., and so on.

• Journal of Applied Biological Chemistry
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• v.48 no.1
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• pp.11-15
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• 2005

Salinity of soils in greenhouse has been increased by massive application of fertilizers. Nitrogen fertilizer was most popular, and thus nitrate became the majority of soil salinity. Accumulation of nitrate led to deleterious effects on the growth and development of crops and vegetables. Microbial strains able to utilize nitrate and thus remove excess nitrate from farm land soils were isolated from 15 different soils of greenhouses and plastic film houses. Four strains able to grow in medium containing 50 mM $KNO_3$ were isolated, among which only E0461 showed high capacity of nitrate uptake. Nitrate uptake by E0461 was dependent on culture medium and was increased by addition of tryptone and peptone. Although E0461 was able to grow without tryptone and peptone, growth was slow, and no nitrate uptake was observed. Nitrate appeared to facilitate E0461 growth in the presence of tryptone and peptone. Through kinetic analysis, nitrate uptake was measured at various concentrations of nitrate, and half-life was calculated. Nitrate concentration decreased with increasing incubation period, and plot between half-lives and initial concentrations of nitrate fitted to single exponential function. These results suggest one major factor plays an important role in microbial nitrate uptake.

• The Plant Pathology Journal
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• v.26 no.4
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• pp.346-352
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• 2010

This study was conducted in Bahar and Lalehjin, Hamadan, Iran to assess the biocontrol efficacy of Coniothyrium minitans Campbell against potato white mold caused by Sclerotinia sclerotiorum (Lib.) de Bary under field and greenhouse conditions. In addition, the resistance of common potato cultivars against S. sclerotiorum was determined in a greenhouse experiment. After straw inoculation of six potato cultivars (Pashandi, Istambouli, Agria, Marfauna, Alpha and Spartaan) with S. sclerotiorum, the least disease severity was observed in Spartaan and Marfauna. Agria showed the most susceptibility to S. sclerotiorum. Compared with the healthy control, different concentrations of C. minitans conidia ($10^7$, $10^8$ and $10^9$ conidia/mL) reduced disease severity under greenhouse condition, and a concentration $10^9$ was the most effective treatment. During 2008 and 2009, four field trials were conducted to evaluate the efficacy of C. minitans in different soil and aerial applications on disease incidence of potato white mold. In 2008, soil application of $Contans^{(R)}$ WG (a commercial product of C. minitans) showed the greatest biocontrol capacity whereas soil application of solid-substrate C. minitans was found inferior when compared with other treatments in both Bahar and Lalehjin field sites. In 2009, benomyl application was the most effective treatment in reducing disease incidence in both tested field sites.

• KCID journal
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• v.8 no.2
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• pp.45-54
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• 2001

A plenty of wastes by greenhouse cultivation affect soil and water pollution much more than those by rice cultivation in paddy field. The greenhouse on paddy field has been increased dramatically, however their physical information such as the location an

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.446-452
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• 2010

Five year term study from 2002 to 2006 was carried out to examine the effects of continuous long-term application of swine liquid manure on soil chemical properties including heavy metal contents and yield of tomato (Lycopersicon esculentum) and cucumber (Cucumis sativus L.) in a greenhouse. Treatments were conventional chemical fertilizers and three types of swine slurry; Slurry composting and biofiltration (SCB), Thermophilic aerobic oxidation (TAO), and Bio-mineral water (BMW). Total nitrogen level of the SCB, TAO, and BMW was 0.47%, 0.09%, and less than 0.01%, respectively. The heavy metal contents of the three liquid manures were much lower than the Korean regulation level. The soil phosphorus, potassium, and heavy metal contents after five year continuous application of swine slurry were not significantly higher than those of chemical fertilizer use. Contents of heavy metals in leaves of the crops did not show significant difference among treatments. The levels of copper and zinc, plant essential elements, in leaves were in the range of optimum plant growth. Yields of tomato and cucumber for swine liquid manures were not significantly different from that of chemical fertilizer. The results implied that the three types of swine slurry may not deteriorate soil chemical properties including phosphate and trace elements in greenhouse soils when they are applied as a basal fertilization at a recommended nitrogen rate based on soil testing.

• Journal of Korean Society for Atmospheric Environment
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• v.29 no.6
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• pp.789-800
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• 2013

$N_2O$ and $CH_4$, Greenhouse gas emission, Forest soil, Closed chamber technique, Soil uptake $N_2O$ and $CH_4$ are important greenhouse gases (GHG) along with $CO_2$ influencing greatly on climate change. Their soil emission rates are highly affected by bio-geo-chemical processes in C and N through the land-atmosphere interface. The forest ecosystems are generally considered to be net emission for $N_2O$; however, net sinks for $CH_4$ by soil uptake. Soil $N_2O$ and $CH_4$ emissions were measured at Mt. Taewha in Gwangju, Kyeonggi, Korea. Closed chamber technique was used for surface gas emissions from forest soil during period from May to October 2012. Gas emission measurement was conducted mostly on daytime (from 09:00 to 18:00 LST) during field experiment period (total 25 days). The gas samples collected from chamber for $N_2O$ and $CH_4$ were analyzed by gas chromatography. Soil parameters were also measured at the sampling plot. GHG averages emissions during the experimental period were $3.11{\pm}16.26{\mu}g m^{-2}hr^{-1}$ for $N_2O$, $-1.36{\pm}11.3{\mu}gm^{-2}hr^{-1}$ for $CH_4$, respectively. The results indicated that forest soil acted as a source of $N_2O$, while it acted like a sink of $CH_4$ on average. On monthly base, means of $N_2O$ and $CH_4$ flux during May (spring) were $8.38{\pm}48.7{\mu}gm^{-2}hr^{-1}$, and $-3.21{\pm}31.39{\mu}gm^{-2}hr^{-1}$, respectively. During August (summer) both GHG emissions were found to be positive (averages of $2.45{\pm}20.11{\mu}gm^{-2}hr^{-1}$ for $N_2O$ and $1.36{\pm}9.09{\mu}gm^{-2}hr^{-1}$ for $CH_4$); which they were generally released from soil. During September (fall) $N_2O$ and $CH_4$ soil uptakes were observed and their means were $-1.35{\pm}12.78{\mu}gm^{-2}hr^{-1}$ and $-2.56{\pm}11.73{\mu}gm^{-2}hr^{-1}$, respectively. $N_2O$ emission was relatively higher in spring rather than other seasons. This could be due to dry soil condition during spring experimental period. It seems that soil moisture and temperature mostly influence gas production and consumption, and then emission rate in subsoil environment. Other soil parameters like soil pH and chemical composition were also discussed with respect to GHG emissions.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.143-153
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• 2018

Soil characteristics along with various container lengths have an important role in the early survival rate and growth of seedlings by influencing the seedling quality. This experiment was conducted to investigate the effect of container length and different soil mixtures on the growth of poplar in a greenhouse. Two types of soil, homogeneous vs. heterogeneous, were used along with two container lengths (30 vs. 60 cm). The heterogeneous soil was made by dividing 50% vermiculite from a mixture of 25% vermicompost and 25% nursery soil in volume. For the homogeneous soil, the above three soil types were mixed together. Populus euramericana clone cuttings were planted in late April, and then, the growth height, root collar diameter (RCD) and biomass were measured in August. The height of the poplar was not significantly affected by container length and soil type, but the RCD was significantly affected by soil type. Leaf and root biomass was higher at the long container than at the short container for both soil treatments, but stem biomass was lower at the heterogeneous soil than at the homogeneous soil treatment. Root to shoot biomass ratio was higher at the heterogeneous soil treatment than at the homogeneous soil treatment by 12%. In conclusion, heterogeneous soil along with a long container is suitable to increase the carbon allocation into the root.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.248-255
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• 2011

For the environmental friendly soil management on the cultivation of crops in the greenhouse, organic materials, such as the by product-fertilizer derived from livestock manure, rice straw, mushroom media, rice hulls, wood sawdust, and cocopeat, were used as carbon sources adjusting the ratio of carbon to nitrogen to 10, 20, and 30 based on the inorganic soil N. In each C/N ratio of greenhouse soil, watermelon was cultivated in the greenhouse as crop for experiment for the spring and summer of the year and the experimental results were summarized as follows. The concentration of T-C in the organic materials applied were between $289{\sim}429g\;kg^{-1}$, In the C/N ratio of 10, using watermelon as the crop cultivated during the second half of the year in the greenhouse soil, the $NO_3$-N and EC were reduced by 21 to 37%, and 26 to 33%, respectively, except the by product-fertilizer from livestock manure, compared to the soil $NO_3$-N and EC used in the experiment. After the watermelon was cultivated in soils that C/N ratios were controlled as 10, 20, and 30 with wood sawdust adding as carbon sources in the three soils with the different EC values, EC values of the soils were reduced by 33, 42, and 39%, respectively, compared to the soil EC used in the experiment. The weight of watermelon was 10.1-13.4 kg per one unit, and, of the three soils with different EC values. In the soils with three different EC values controlled at C/N ratio of 20, the weight of watermelon was good. The degree of sugar of watermelon were 11.8 to 12.3 Brix, which means that the difference between the treatments was not significant. In conclusion, the C/N ratio of 20 controlled by the proper supply of organic materials according to the representative EC values shown in the greenhouse soils was optimal condition enough to maintain the soil management for the organic culture with the proper nutrient cycling.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.2
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• pp.181-193
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• 2016

This experiment was conducted to evaluate the effect of carbonized rice hull (CRH) application on soil carbon storage and $N_2O$ emissions from upland soil. It was used at different rates of 0, 5, 10 and $20Mg\;ha^{-1}$. During the Chinese cabbage cultivation, several soil chemical characteristics such as soil moisture, temperature and soil carbon were observed. Also, $CO_2$ and $N_2O$ emissions were monitored. Soil organic matter contents slightly increased with carbonized rice hull applied in all the treatments. The soil carbon contents with application rate of 0, 5, 10 and $20Mg\;ha^{-1}$ were 0, 1.3, 1.2 and $2.6g\;kg^{-1}$, respectively. It was observed that soil carbon content was higher with increasing CRH application rate. Total nitrogen contents of soil applied with CRH relatively decreased with the course of time. However, $NO_3$-N contents in the soil with CRH application rate of 5, 10 and $20Mg\;ha^{-1}$ were 28.6, 25.7 and $21.5mg\;kg^{-1}$ at the end of experiment, respectively. $CO_2$ emission at the $5Mg\;ha^{-1}$ application of CRH was higher about 18.9% than non-treatment, whereas those of $10Mg\;ha^{-1}$ and $20Mg\;ha^{-1}$ treatment were lower 14.4% and 11.8% compared to non-treatment, respectively. Also, it was shown that $N_2O$ emission reduced by 19.9, 28.3 and 54.0% when CRH was applied at 5, 10 and $5Mg\;ha^{-1}$, respectively.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.411-417
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• 1999

This study was performed to figure out an optimum water environment and to obtain the fundamental data related with saving labor and water consumption for the chinese cabbage being grown in greenhouse . The productivity of cabbage cultivated in boty pots and floor were compared to each other in the aspects of height and weight depending on the soil saturation levels. Obtained results are as follows. ; In case of pot cultivation , the height as well as weight of cabbage in 80% soil saturation level(P80) were measured to be larger than those in the other 2 soil saturation leves (P100 and P60). The weight of floor cultivated cabbages were relatively larger than that of pot cultivated ones. In accordance with saturation ration, the general trend of water consumption rate was maximum in P80 and was decreased in the order of P80 , P100 and P60. And the average indoor temperature as well as the plant growth rate were found to be closely related with water consumption rate.